At $8.95 apiece, $1100 can buy you 122 mass-market paperbacks. I certainly hope that someone can bring that retail price down a fair chunk, or this tech is not going far.
This is not meant for reading paperbacks. A kindle paperwhite, at $120, is a far better choice for that.
This is for reading and annotating documents, and generally replacing paper in an office or academic setting. Given then number of research papers I've printed out (thousands and thousands of pages), I can see a huge use for this. It may still not be cost effective, but is still much more environmentally friendly and saves the hassle of keeping track of all of that paper.
The paperless office has been an idea for several decades, but without devices like this that allow easy reading and annotation, we haven't been able to get there.